過渡金屬摻雜氧化鈦催化材料的設計合成及其Fenton催化性能研究
發(fā)布時間：2018-08-30 20:36
【摘要】：過渡金屬離子摻雜型異相Fenton催化劑在有機污染物催化降解中具有顯著優(yōu)勢,能夠有效克服均相Fenton催化劑在應用中受pH的限制、難以回收、容易造成二次污染等弊端,同時可以解決負載型異相Fenton催化劑活性組分易脫落的問題。但在催化過程中,過渡金屬離子容易失活,即難以從氧化態(tài)形式有效轉化為還原態(tài)形式,導致催化劑的循環(huán)使用性能較差。針對此,本論文提出利用摻雜基底來促進過渡金屬離子還原恢復的設想,即通過摻雜基底與過渡金屬離子之間可能的電荷傳遞,促進過渡金屬離子的有效再生,從而獲得長效穩(wěn)定的異相Fenton催化劑。本論文首先采用密度泛函方法對Mn(II)摻雜的銳鈦型TiO2進行模擬計算,從理論角度揭示出TiO2基底對錳離子的還原再生具有明顯的促進作用。然后,通過“溶膠凝膠—氨水刻蝕—離子交換—灼燒”法合成出Mn摻雜的花狀TiO2納米材料(Mn-fTiO2),并證實Mn-fTiO2在催化降解多種染料的應用中顯示出優(yōu)異的催化活性和穩(wěn)定性。在此基礎上,我們進一步設計合成了系列過渡金屬離子(Mn2+、Cu2+、Co2+、Ni2+)摻雜的花狀氧化鈦材料,并探究其對有機染料的催化降解效果,通過與均相催化體系進行對比研究,也證實了TiO2基底對于這些過渡金屬離子催化活性具有明顯的促進效果。主要研究內容及結論如下:1、建立了錳離子摻雜TiO2催化劑的結構模型,通過密度泛函方法,模擬H2O2在其表面的的反應路徑(以甲醇為底物)。結果表明TiO2基底可促進Mn的還原再生,同時基底自身也易于恢復。進一步,采用“溶膠凝膠—氨水刻蝕—離子交換—灼燒”方法合成出Mn-fTiO2納米材料,通過SEM、XRD、UV-DRS、XPS、BET等表征分析方法確定其物理化學性質,進一步考察了其對亞甲基藍(MB)等有機染料的Fenton催化降解性能。結果證實Mn-fTiO2為單分散、球形、花狀形貌,具有良好的銳鈦礦晶型、較大的比表面積、Mn的摻雜形態(tài)為+2價;催化降解MB時表現(xiàn)出優(yōu)異的Fenton催化性能;通過設計對照實驗,確認了基底對Mn氧化還原存在明顯的促進作用;另外,該材料對多種有機染料均表現(xiàn)出高效的催化降解性能,在多次循環(huán)使用之后仍保持穩(wěn)定的催化活性。2、基于上述研究結果,我們以無定型TiO2(pTiO2)、乙二醇(EG)、乙二胺(EDA)、過渡金屬鹽等試劑為原料,發(fā)展出制備不同過渡金屬離子摻雜TiO2的一種簡單且通用性方法,合成出Mn2+、Cu2+、Co2+、Ni2+等摻雜的花狀TiO2納米材料。采用SEM、XRD、UV-DRS、XPS、BET等技術手段表征材料的物理化學性質。選用MB為模型降解底物,探究所合成的系列過渡金屬離子摻雜氧化鈦材料對有機染料的催化降解效果。表征結果顯示,四種過渡金屬離子摻雜材料均表現(xiàn)為單分散的球形花狀形貌,具有結晶性優(yōu)良、比表面積大等特點,四種離子的摻雜形態(tài)均為+2價;催化降解實驗結果表明,四種材料對MB均表現(xiàn)出良好的催化活性,且活化能較小,反應容易進行;經設計對照實驗,證實基底TiO2對四種過渡金屬離子的還原再生均存在一定的促進作用;選取其中Mn2+、Co2+摻雜的兩種材料分別考察其催化穩(wěn)定性,發(fā)現(xiàn)循環(huán)使用5次之后其催化效率無明顯衰減。
[Abstract]:Transition metal ion doped heterogeneous Fenton catalyst has obvious advantages in catalytic degradation of organic pollutants. It can effectively overcome the shortcomings of homogeneous Fenton catalyst which is limited by pH, difficult to recover and easy to cause secondary pollution in application. At the same time, it can solve the problem that active components of supported heterogeneous Fenton catalyst are easy to fall off. In the catalytic process, transition metal ions are easy to deactivate, that is, it is difficult to effectively convert from oxidized to reduced forms, resulting in poor recycling performance of the catalyst. In this paper, the density functional theory (DFT) method is used to simulate the Mn(II)-doped anatase titanium dioxide. It is revealed that the substrates of titanium dioxide can promote the reduction and regeneration of manganese ions. Mn-doped flower-like titanium dioxide nanomaterials (Mn-fTiO2) were synthesized by gel-ammonia etching-ion exchange-burning method. It was confirmed that Mn-fTiO2 exhibited excellent catalytic activity and stability in the catalytic degradation of various dyes. On this basis, we further designed and synthesized a series of transition metal ions (Mn2+, Cu2+, Co2+, Ni2+). The doped flower-like titania and its catalytic degradation effect on organic dyes were investigated. By comparing with homogeneous catalytic system, the catalytic activity of these transition metal ions on the titania substrate was also confirmed. The main research contents and conclusions are as follows: 1. The junction of Mn-doped titania catalyst was established. The results show that the TiO2 substrate can promote the reduction and regeneration of Mn, and the substrate itself can be easily restored. Furthermore, Mn-fTiO2 nano-materials were synthesized by sol-gel-ammonia etching-ion exchange-burning method. The Mn-fTiO2 nano-materials were characterized by SEM, X-ray diffraction. RD, UV-DRS, XPS, BET and other characterization methods were used to determine its physical and chemical properties, and the Fenton catalytic degradation of methylene blue (MB) and other organic dyes was further investigated. In addition, the material exhibits high catalytic degradation performance for various organic dyes and remains stable catalytic activity after repeated recycling. 2. Based on the above results, we have no definite conclusion. A simple and universal method for preparing different transition metal ions doped titanium dioxide was developed. Mn2+, Cu2+, Co2+, Ni2+ doped flower-like titanium dioxide nanomaterials were synthesized. The physical and chemical properties of the materials were characterized by SEM, XRD, UV-DRS, XPS and BET. The catalytic degradation of organic dyes by a series of transition metal ions doped titanium oxide materials was investigated. The results showed that all the four transition metal ions doped materials exhibited monodisperse spherical flower-like morphology, good crystallinity, large specific surface area and four kinds of ions doped. The results of catalytic degradation experiments show that the four materials have good catalytic activity for MB, and the activation energy is small, and the reaction is easy to proceed. The comparison experiments prove that the substrates of titanium dioxide can promote the reduction and regeneration of four transition metal ions to a certain extent. It was found that the catalytic efficiency of the catalyst was not attenuated after 5 cycles.
【學位授予單位】：中國地質大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：O643.36
本文編號：2214219
[Abstract]:Transition metal ion doped heterogeneous Fenton catalyst has obvious advantages in catalytic degradation of organic pollutants. It can effectively overcome the shortcomings of homogeneous Fenton catalyst which is limited by pH, difficult to recover and easy to cause secondary pollution in application. At the same time, it can solve the problem that active components of supported heterogeneous Fenton catalyst are easy to fall off. In the catalytic process, transition metal ions are easy to deactivate, that is, it is difficult to effectively convert from oxidized to reduced forms, resulting in poor recycling performance of the catalyst. In this paper, the density functional theory (DFT) method is used to simulate the Mn(II)-doped anatase titanium dioxide. It is revealed that the substrates of titanium dioxide can promote the reduction and regeneration of manganese ions. Mn-doped flower-like titanium dioxide nanomaterials (Mn-fTiO2) were synthesized by gel-ammonia etching-ion exchange-burning method. It was confirmed that Mn-fTiO2 exhibited excellent catalytic activity and stability in the catalytic degradation of various dyes. On this basis, we further designed and synthesized a series of transition metal ions (Mn2+, Cu2+, Co2+, Ni2+). The doped flower-like titania and its catalytic degradation effect on organic dyes were investigated. By comparing with homogeneous catalytic system, the catalytic activity of these transition metal ions on the titania substrate was also confirmed. The main research contents and conclusions are as follows: 1. The junction of Mn-doped titania catalyst was established. The results show that the TiO2 substrate can promote the reduction and regeneration of Mn, and the substrate itself can be easily restored. Furthermore, Mn-fTiO2 nano-materials were synthesized by sol-gel-ammonia etching-ion exchange-burning method. The Mn-fTiO2 nano-materials were characterized by SEM, X-ray diffraction. RD, UV-DRS, XPS, BET and other characterization methods were used to determine its physical and chemical properties, and the Fenton catalytic degradation of methylene blue (MB) and other organic dyes was further investigated. In addition, the material exhibits high catalytic degradation performance for various organic dyes and remains stable catalytic activity after repeated recycling. 2. Based on the above results, we have no definite conclusion. A simple and universal method for preparing different transition metal ions doped titanium dioxide was developed. Mn2+, Cu2+, Co2+, Ni2+ doped flower-like titanium dioxide nanomaterials were synthesized. The physical and chemical properties of the materials were characterized by SEM, XRD, UV-DRS, XPS and BET. The catalytic degradation of organic dyes by a series of transition metal ions doped titanium oxide materials was investigated. The results showed that all the four transition metal ions doped materials exhibited monodisperse spherical flower-like morphology, good crystallinity, large specific surface area and four kinds of ions doped. The results of catalytic degradation experiments show that the four materials have good catalytic activity for MB, and the activation energy is small, and the reaction is easy to proceed. The comparison experiments prove that the substrates of titanium dioxide can promote the reduction and regeneration of four transition metal ions to a certain extent. It was found that the catalytic efficiency of the catalyst was not attenuated after 5 cycles.
【學位授予單位】：中國地質大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：O643.36
【參考文獻】
相關期刊論文 前10條
1 張文慧;;從世界人口增長的角度分析未來資源科學發(fā)展的重大內容[J];軍民兩用技術與產品;2014年07期
2 王彥斌;趙紅穎;趙國華;王宇晶;楊修春;;基于鐵化合物的異相Fenton催化氧化技術[J];化學進展;2013年08期
3 閆龍;王玉飛;李健;劉慧瑾;;工業(yè)廢水常規(guī)處理方法概述[J];榆林學院學報;2013年04期
4 王曉兵;胡國強;;溶劑萃取法對甲酸廢水的處理研究[J];遼寧石油化工大學學報;2009年03期
5 王慧;周月霞;柏仕杰;鄭天凌;;染料廢水生物法處理技術的研究進展[J];廈門大學學報(自然科學版);2008年S2期
6 范迪;王娟;遲宏;;海水資源開發(fā)及綜合利用淺析[J];海洋科學;2008年03期
7 楊少斌;費學寧;張建博;;電化學氧化技術在印染廢水處理中的應用[J];廣東化工;2008年02期
8 呂后魯;劉德啟;;工業(yè)廢水處理技術綜述[J];石油化工環(huán)境保護;2006年04期
9 趙月龍;祁佩時;楊云龍;;高濃度難降解有機廢水處理技術綜述[J];四川環(huán)境;2006年04期
10 方旭,付振強,韓宏大;復合式好氧生物法處理印染廢水[J];環(huán)境保護科學;2004年03期
，本文編號：2214219
本文鏈接：http://sikaile.net/kejilunwen/huaxue/2214219.html
教材專著
